Eruptive Stars
Monitoring

Recurrent Symbiotic Nova T CrB
(Pre Outburst spectroscopic monitoring: 2022 - 202X)

Retour

Context	T CrB belongs to the very small group of recurring novae (RN) and among them the symbiotic sub-group (SyRN). Its first outburst was detected in 1866 during which Huggins obtained the first spectrum of a nova. The second outburst occurred in 1946, making T CrB a recurring nova. The system is currently in low state since after a "big active phase" from late 2014 to 2023-04. From a comparison with 1946 event, Brad Scheafer (2019) predicted the next outburst around 2023. The last published prediction is April-September 2024 But Luna+ (2020) considering the lower activity of the current high state delayed the prevision to 2023-2029 from an estimation of the accretion rate.
Date of the outburst Predictions		S1 S2 S3: Scheafer (2019-07,2023-06,2023-09) M+:Maslennikova (2023) L+: Luna & al. (2020) blue dot: periastron. triangle: current date
Current status (2024-08-08)	Orbital variations, low state activity
Journal 2023 - 2024	The high active state (late 2014-April 2023) is over (ATel # 16109) The high cadency spectroscopic monitoring by ARAS group allows to detect precisely the stepped decrease of ionization on JD 2460048 +/- 6. B & V luminosities returned to pre-active states values and follow a double wave orbital cycle. The relative intensities of emission lines HI, HeI, HeII decline at roughly the level observed in 2013-2014. May 2024: short flare of Balmer lines from JD 2460439.5 to 447.5 (+/- 0.5) . Flux (H alpha) reaches 8 E-12 erg/cm^2/s around JD 2460443.5 (+/- 0.5)
Update: 2024-08-08

 

Recent Spectrum

 

 

AAVSO BV Bands		B and V luminosity according to the orbital phase. The current cycle in black. Orbital Phase: Lines, 1988 P = 227.67 d JD0= 2435687.6 ("conjunction with M3III behind")

 

 

 

Spectroscopic Evolution 2023-2024
2023-04: End of the "big active phase"
2023: very low activity
		Flux H alpha from flux calibrated spectra

Spectroscopic Evolution		T
2013-2023
		One of the key feature of the evolution of the sytem during the high state 2015-2023 (big active phase, according the terminomogy suggested by Ielkiewicz+ 2016) is the intensity of He II 4686 line (see e.g. Ilkiewicz+, 2016) The spectra acquired in 2023 show the fast decrease of He II. The high cadency monitoring allows to detect precisely the stepped decrease of ionization on JD 2460048 +/- 6. ATel#16109 T CrB: the active spectroscopic phase (2015-2023) is over https://www.astronomerstelegram.org/?read=16109

 

 

Temporary recent H alpha profiles compared to the pseudo-continuum of a red giant M4III spectra T CrB : Joan Guarro spectrum M4 III : Francois Teyssier spectroscope: echelle NOUT R = 9000 The HI zone dominates the nebula

 

Eruptive Stars Database	https://aras-database.github.io/database/tcrb.html
Topic in ARAS Forum	https://spectro-aras.com/forum/viewtopic.php?t=2902&start=30

 

 

Observers 2023- to date

J.D. Hinnefeld, I. Diabassoura, F. Sims, A. Leduc, F. Teyssier, S. Curry, D. Boyd, D. Cujedo, J. Guarro Flo, C. Buil, G. Bertrand, E. Bertrand, X. Dupont, S. de Vischer, J. R. Foster, C. Boussin R. Leabeater, C. Laulhère, J. Michelet, 2SPOT, K. Shank, V. Marie, V. Lecocq, C. Buil, G. Bertrand,

Observers 2012-2022

F. Sims, P. Somogyi, J. Guarro Flo, F. Teyssier, I. Diabassoura, D. Boyd, C. Boussin, P.A. Dubovsky, T. Lester, F. Campos, A. Leduc, K. Shank, V. Lecoq, S. Curry, , J.R. Foster J. Montier, L. Franco, U. Sollecchia, C. Buil, K. Graham, V. Bouttard, T. Medulka, CDZ, J. Martin,  J. Michelet, M. Rodriguez, R. Ehlert, P. Cazatto, O. Garde, F. Boubault, M. Verlinden, Y. Markus, P. Berardi,  S. de Visscher, X. Dupont, G. Bertrand, J. Coffin, M. Le Lain, C. Laulhere, R Ehlert, J.D. Hinnefeld, J. Lecomte, S. Charbonnel, G. Martineau, Y. Buchet, J.P. Godard, T. Rodda, E. Bertrand, H. Boussier, J.B.  Desrosiers, J.P. Masviel, D. Li, C. Revol, A.J. Wilson, C. Kreider

 

 

 

Monitoring:

Spectra T CrB Eruptive Stars Database: https://aras-database.github.io/database/tcrb.html

References:

Schaefer, B. E, MNRAS, 2023 https://arxiv.org/pdf/2303.04933.pdf
Schaefer, B. E, AAS, 2019 https://ui.adsabs.harvard.edu/abs/2019AAS...23412207S/abstract
Luna, G.J.M, Sokoloski J.L., Mukai K., and Kuin, N.P.M, 2020, ApJ https://arxiv.org/pdf/2009.11902.pdf
Iłkiewicz, K., Mikołajewska, J., Stoyanov, K., Manousakis, A., Miszalski, B., MNRAS, 2016 https://ui.adsabs.harvard.edu/abs/2016MNRAS.462.2695I/abstract

2023-2024

https://arxiv.org/pdf/2307.00255.pdf
The "Super-Active" Accretion Phase of T CrB has Ended
Munari, Ulisse
Research Notes of the AAS, Volume 7, Issue 7, id.145.

ATel #16107 2023-06-30
https://www.astronomerstelegram.org/?read=16107
T CrB: the active spectroscopic state (2014-2023) is over
 F. Teyssier, J. D. Hinnefeld, C. Boussin, I. Diabassoura , J. Guarro Flo, F. Sims, A. Leduc, S. Curry, D. Boyd, D. Cujedo (ARAS Group), S. N. Shore (Univ. of Pisa)

ATel #16107 2023-06-30
https://www.astronomerstelegram.org/?read=16107
Recurrent nova T CrB has just started its Pre-eruption Dip in March/April 2023, so the eruption should occur around 2024.4 +- 0.3
Bradley E. Schaefer (Louisiana State Univ.), Brian Kloppenborg (AAVSO), Elizabeth O. Waagen (AAVSO), and the AAVSO observers

ATel #16114 2023-07-03
https://www.astronomerstelegram.org/?read=16114
Swift observations of the changes in the brightness of the recurrent nova T CrB
N Paul Kuin (MSSL), Gerardo Juan Manuel Luna (CONICET/ U. of Hurlingham), Kim Page (Leicester U), Koji Mukai (NASA/GSFC & UMBC), Jennifer L Sokoloski (Columbia U), Julian P. Osborne (Leicester U), Bradley E. Schaefer (Louisiana U)

ATel #16023 2023-04-30
https://www.astronomerstelegram.org/?read=16023
Strong flickering from the recurrent nova T Coronae Borealis ATel #16023
M. Minev, R. Zamanov, K. Stoyanov (Institute of Astronomy and NAO, Bulgarian Academy of Sciences)

ATel #15916 2023-02-28
https://www.astronomerstelegram.org/?read=15916
Persistent flickering of T CrB during the high activity state pre-nova outburst phase
S. N. Shore (Univ. Pisa), F. Teyssier (ARAS Group)